### Adding `env_logger` for Rust Tests

Source: https://github.com/rust-cli/env_logger/blob/main/README.md

These commands add `log` as a regular dependency and `env_logger` as a development dependency, which is the recommended setup for using `env_logger` within Rust tests.

```console
$ cargo add log
$ cargo add --dev env_logger
```

--------------------------------

### Running Rust Executable with `RUST_LOG` (INFO level)

Source: https://github.com/rust-cli/env_logger/blob/main/README.md

This example illustrates that the `RUST_LOG` environment variable is case-insensitive for log level names. Setting it to `INFO` achieves the same result as `info`.

```bash
$ RUST_LOG=INFO ./main
```

--------------------------------

### Initializing `env_logger` in a Rust Executable

Source: https://github.com/rust-cli/env_logger/blob/main/README.md

This Rust code snippet demonstrates how to initialize `env_logger` early in the `main` function of an executable. After initialization, `log` macros like `info!` can be used to emit log messages.

```rust
use log::info;

fn main() {
    env_logger::init();

    info!("starting up");

    // ...
}
```

--------------------------------

### Running a Single Rust Test with Logging

Source: https://github.com/rust-cli/env_logger/blob/main/README.md

This command demonstrates how to run a specific Rust test (`it_adds_one`) with `RUST_LOG` enabled for the `my_lib` module, which helps in isolating and debugging individual test cases.

```bash
$ RUST_LOG=my_lib=info cargo test it_adds_one
```

--------------------------------

### Running Rust Executable with `RUST_LOG` (info level)

Source: https://github.com/rust-cli/env_logger/blob/main/README.md

This bash command shows how to execute a compiled Rust binary while setting the `RUST_LOG` environment variable to `info`. This configuration enables the display of log messages at the 'info' level and higher.

```bash
$ RUST_LOG=info ./main
```

--------------------------------

### Configuring `env_logger` in Rust Tests

Source: https://github.com/rust-cli/env_logger/blob/main/README.md

This Rust code demonstrates how to set up `env_logger` within a test module. The `init()` function ensures logging is enabled for each test by using `env_logger::builder().is_test(true).try_init()`, preventing multiple initializations.

```rust
fn add_one(num: i32) -> i32 {
    info!("add_one called with {}", num);
    num + 1
}

#[cfg(test)]
mod tests {
    use super::*;
    use log::info;

    fn init() {
        let _ = env_logger::builder().is_test(true).try_init();
    }

    #[test]
    fn it_adds_one() {
        init();

        info!("can log from the test too");
        assert_eq!(3, add_one(2));
    }

    #[test]
    fn it_handles_negative_numbers() {
        init();

        info!("logging from another test");
        assert_eq!(-7, add_one(-8));
    }
}
```

--------------------------------

### Running Rust Tests with Module-Specific Logging

Source: https://github.com/rust-cli/env_logger/blob/main/README.md

This bash command shows how to run Rust tests while filtering log messages to only display 'info' level messages from the `my_lib` module, useful for focused debugging.

```bash
$ RUST_LOG=my_lib=info cargo test
```

--------------------------------

### Adding `env_logger` and `log` to Project Dependencies

Source: https://github.com/rust-cli/env_logger/blob/main/README.md

This command adds the `log` and `env_logger` crates as dependencies to your Rust project, which is necessary for using `env_logger` in executables.

```console
$ cargo add log env_logger
```

--------------------------------

### Configuring `env_logger` to Log to Standard Output

Source: https://github.com/rust-cli/env_logger/blob/main/README.md

This Rust snippet illustrates how to use `env_logger::Builder` to explicitly set the log target to standard output (`Stdout`) instead of the default standard error (`Stderr`).

```rust
use std::env;
use env_logger::{Builder, Target};

let mut builder = Builder::from_default_env();
builder.target(Target::Stdout);

builder.init();
```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.